Melancholia won her an award at Cannes – and plunged her into controversy. The actor talks about Von Trier’s Nazi moment, her battle with depression – and Charlotte Gainsbourg’s breasts Melancholia begins with a wedding and ends with a funeral. Actually, the new film from Danish provocateur Lars von Trier ends with the apocalypse – a funeral for everyone, as a vast planet rears up on the near horizon, lighting up the lawn and setting the birds chattering. Watching the movie at this year’s Cannes film festival, Kirsten Dunst was surprised to find herself giggling, as if this was some sort of happy ending. “That’s one thing you can say for the end of the world,” she says. “It solves a lot of problems.” We’re drinking coffee in the basement of a London hotel, with embroidered snowflakes on the wallpaper and an Indian summer raging outside. The actor is attired as though for a night on the town – sheer black dress, jingling silver bracelet – even though it’s mid-morning and she has yet to eat breakfast. She confesses that she keeps staring at the snowflakes, her eyes glazing over, her mind zoning out. At lunchtime, she is due to board a flight home to New York, after which she has a clean slate for the rest of the year. You get the impression she can’t wait to put 2011 behind her. Certainly, Melancholia has been a torrid passage for its 29-year-old star: a typical Von Trier rollercoaster that places soaring triumph cheek-by-jowl with low-comedy disaster. On the upside is Dunst’s performance, a role that is worlds away from the studio fluff that has taken too much of her recent energies. She plays Justine, the brilliant, dark-eyed manic-depressive heroine, who stumbles through the worst wedding ceremony this side of Festen and then belatedly comes into her own as judgment day looms. It’s a devastating performance, and one that